Why do php errors appear on mac os?

Question

PHP

Hello! I installed nginx php-fpm on my mac, the server is working fine, the sites on drupal are installed and working correctly, but with the drush command, two errors will always appear.

Warning: PHP Startup: Unable to load dynamic library '/usr/local/Cellar/php55/5.5.21/lib/php/extensions/no-debug-non-zts-20121212/php_gd2.dll' - dlopen(/usr/local/Cellar/php55/5.5.21/lib/php/extensions/no-debug-non-zts-20121212/php_gd2.dll, 9): image not found in Unknown on line 0
PHP 5.5.21 (cli) (built: Feb  7 2015 08:37:54) 
Copyright (c) 1997-2014 The PHP Group

The same thing shows after the php -v command, php itself is not selenium, tell me how to solve this problem? Thank you!